My dad has a felony from when he was 18 for driving with a suspended license.

This doesn't sound correct. I'm unaware of any jurisdiction anywhere in which a first offense driving with a suspended license (on its own) is a felony.

Out of fear of being arrested he begged my dad to hide the gun when they became aware the cops were coming.

This is a pretty bad fact for both your brother and father.

I'm not your lawyer, or your family's lawyer, but generally speaking your brother's probation is very likely in jeopardy. Your father and brother are potentially looking at some relatively serious firearms licensing, sale, and operation charges too. But this depends to a great extent on your local rules & DAs.

Congratulations, your comment currently holds the #1 spot for "/r/legaladvice understatement of the decade." Since I believe it is impossible for any statement made in the next 6 years to be more of an understatement, we're going ahead and giving you the award now:

I wanted to communicate the fact that the OP's father almost certainly did something incredibly unwise to manage to get a felony driving on suspended, and that given the rest of the post it is clear doing things that are incredibly unwise seems to be commonplace in this family. That was my attempt at doing so in the kindest way possible.

He was stopped multiple times for driving with a suspended license, he basically ignored his suspension because he had to get to work to provide for my brother and myself. I believe he served a year per the 3 strike rule or something along those lines. He found that he was eligible to get the felony removed from his record and was planning on paying the fee and submitting the paperwork this week so that he could legally buy guns. My brother was not arrested, he's on probation and had served a month for an aggravated DWI. He was 18 years old with a BAC of .03 and hit a parked car resulting in enough property damage to warrant a felony. He served a month with 11 months suspended and a year of probation and managed to avoid getting his case charged as a felony.

My father recently bought a parts kit for an AK47, built it, cut off a piece so that it would only function as a semi-automatic rather than automatic

What he did was buy an AK-47 parts kit and built it on an existing receiver or re-welded one that was cut up and included with the kit. My guess is that he went the re-welding route because he would be unable to purchase an AK-47 receiver through an FFL with a felony on his record. The receiver is the part of the rifle that the ATF considers to be the firearm.

cut off a piece so that it would only function as a semi-automatic rather than automatic

No such thing.

test firing it in the woods

Felon in possession of a firearm. Your Dad is prohibited by federal law from possessing firearms or ammunition. Violating these laws can net him 10 years of imprisonment and/or a $250,000 fine

The Feds might charge him later for those crimes.

EDIT: Why were the cops called? I live in NH and it's perfectly legal to shoot guns in the woods unless you're within 300 feet of a dwelling or if you shoot across a road.

I believe he received most of the parts with a flat receiver. He had to drill some of the holes, shape it, heat treat it, and do some rivets.

My guess is that he was shooting in a sand pit that he was given verbal permission to use by the owner about a year ago. He's usually a few hundred yards away from the road so I wouldn't be surprised if a passing cop saw his car on the side of the road and possibly heard gunshots so went to investigate.

I believe he had accidentally received a part that would have allowed the gun to shoot full-auto and so did what was necessary to make this no longer possible before ever firing the gun. I'm not 100% on those details.

He got the kit off of a guy on armslist, I'm pretty sure the parts were all from the same gun aside from the receiver. It was a really nice kit and the gun came out awesome, but he made 100% sure that it was completely incapable of firing as an automatic because he didn't have any interest in getting in trouble for something like that.

While messing around with the gun after building it, but without any ammo ever going through the gun, he was basically just making sure everything worked smoothly and realized that it wasn't locking up when he put it in full auto and held the trigger. He basically just made sure that that stopped happening.

He got the kit off of a guy on armslist, I'm pretty sure the parts were all from the same gun aside from the receiver. It was a really nice kit and the gun came out awesome, but he made 100% sure that it was completely incapable of firing as an automatic because he didn't have any interest in getting in trouble for something like that.
While messing around with the gun after building it, but without any ammo ever going through the gun, he was basically just making sure everything worked smoothly and realized that it wasn't locking up when he put it in full auto and held the trigger. He basically just made sure that that stopped happening.
I guess they told him there won't be any federal charges or gun charges, though I don't know if that will end up being the case. They charged him with felony trespassing (he didn't cause any property damage which is what defines felony trespassing by my understanding; apparently the owner of the property who gave him permission passed away a few months ago without his knowledge so he's trying to get in contact with someone who knew he had been given permission and was associated with the guy), reckless conduct, and drug possession (they found 3 roaches in his ashtray which probably added up to about half a gram, and took not only the roaches but also his ashtray as evidence).

Well I have bought plenty of things on armslist. And while I think it's certainly possible that he received some parts that when assembled malfunctioned into full auto, I think the likelihood of it is pretty slim.

If your Dad is really a felon he should never have even touched a gun. Hell, he shouldn't ever possess as much as one bullet. The federales do not screw around with that charge, it's usually a slam dunk and people do serious time for it.

I believe he had accidentally received a part that would have allowed the gun to shoot full-auto

If he bought the kit online or in a store it didn't contain any full auto parts, per se. They're not sold with true full auto parts and a conversion requires additional receiver milling and the knowledge to set the proper mechanical timing. And if he did have true FA parts and they aren't registered pre-1986 parts, it's a whole heap of trouble. Getting caught with those - felon or not a felon -will definitely land you in federal prison.

based on the whole of what you've posted and what your dad is charged with, he could be in some serious trouble. sounds like there aren't any federal charges yet, but there could be - weapons dealing, purchasing weapons through a straw purchase, felon in possession of a firearm, who knows what else.

the stuff he is charged with now is not quite as serious, but the charges from the police are not the ones to worry about. it's what the DA decides to charge him with once they get the police reports and run his record.

Your dad needs an attorney if he hopes to mitigate the consequences to the greatest extent possible. If he qualifies for a public defender, he should use one. If not, he needs to hire one.

I know you may not be welcome to this, but I think it may be helpful. I come from a dysfunctional family. Obviously, you do too. Your dad and your brother are making very very very bad decisions. The kind we hope most people will mature out of before they get out of their teenage years.

You need to break that cycle, and not treat as normal or acceptable the majority of these behaviors. That does not mean you should not love them or appreciate the work they have put in to support you.

It does mean you should make a habit of much better decisions. Feel free to be pissed I said this, but I would prefer you to be pissed if there is a chance of you actually thinking through this and not following in your dad/brothers footsteps.

Believe me, I don't agree with their decisions and I make sure they know it. I have my shit together and I've never been in any legal trouble, I like to think that I'm pretty smart and I'm well aware that they generally aren't.

but he made 100% sure that it was completely incapable of firing as an automatic

Great idea.

While messing around with the gun after building it, but without any ammo ever going through the gun, he was basically just making sure everything worked smoothly and realized that it wasn't locking up when he put it in full auto and held the trigger. He basically just made sure that that stopped happening.

An AK-47 wouldn't function at all without ammo in it.

I guess they told him there won't be any federal charges or gun charges

I would be surprised if that is the case. Felon in possession is a slam-dunk case and a lot of DAs love them for that reason.

Either your Dad is not actually a felon, or the incident didn't quite happen like he told you.

I mean when he was cocking the gun then holding the trigger the hammer would lock into place when on semi-auto, it would not lock into place in full-auto. At least I'm pretty sure that's what was going on. Either way, there was a clear distinction between when he set the gun to semi and when he set it it auto, which worried him.

He had a low class non-violent felony, it was based on driving offenses, and he was eligible to have it stricken from his record pending some paperwork and a $300 fee. It was only marked as a felony as a technicality due to the number of offenses he had been charged with. That may have had something to do with it, or he may just be putting false faith in the officers (or not have fully understood them). As far as I know he never actually had any gun stores do a background check, he was always honest about having a felony and so never attempted to buy a gun from a dealer.

He had a low class non-violent felony, it was based on driving offenses, and he was eligible to have it stricken from his record pending some paperwork and a $300 fee. It was only marked as a felony as a technicality due to the number of offenses he had been charged with. That may have had something to do with it, or he may just be putting false faith in the officers (or not have fully understood them).

That's cool and all, but a felony is a felony. I wouldn't put faith in any officers for any reason. It's the DA and the feds he has to worry about.

Listen, I'm not questioning your understanding of the story or anything like that, it's just that he could be facing some serious charges. And based on what you've said it sounds as if he might not make the best choices all the time and he might not be telling you the whole story.

He apparently just got released. He's being charged with reckless conduct, falsifying police evidence, and trespassing. I apologize for not having more detailed information, I've been at work all day and I'm still not out for a few more hours. All of my information is coming from correspondence with my hysteric mom.

And I just want to point out to everyone that I'm aware they made extremely unintelligent decisions. My dad and brother have never made the best decisions, I myself have a crystal clear record and I understand that any consequences are a reflection of their poor choices. I'm just trying to make the whole situation a bit clearer.